| Step | Hyp | Ref | Expression | 
						
							| 1 |  | pmtrdifel.t |  |-  T = ran ( pmTrsp ` ( N \ { K } ) ) | 
						
							| 2 |  | pmtrdifel.r |  |-  R = ran ( pmTrsp ` N ) | 
						
							| 3 |  | pmtrdifwrdel.0 |  |-  U = ( x e. ( 0 ..^ ( # ` W ) ) |-> ( ( pmTrsp ` N ) ` dom ( ( W ` x ) \ _I ) ) ) | 
						
							| 4 |  | wrdsymbcl |  |-  ( ( W e. Word T /\ x e. ( 0 ..^ ( # ` W ) ) ) -> ( W ` x ) e. T ) | 
						
							| 5 |  | eqid |  |-  ( ( pmTrsp ` N ) ` dom ( ( W ` x ) \ _I ) ) = ( ( pmTrsp ` N ) ` dom ( ( W ` x ) \ _I ) ) | 
						
							| 6 | 1 2 5 | pmtrdifellem1 |  |-  ( ( W ` x ) e. T -> ( ( pmTrsp ` N ) ` dom ( ( W ` x ) \ _I ) ) e. R ) | 
						
							| 7 | 4 6 | syl |  |-  ( ( W e. Word T /\ x e. ( 0 ..^ ( # ` W ) ) ) -> ( ( pmTrsp ` N ) ` dom ( ( W ` x ) \ _I ) ) e. R ) | 
						
							| 8 | 7 3 | fmptd |  |-  ( W e. Word T -> U : ( 0 ..^ ( # ` W ) ) --> R ) | 
						
							| 9 |  | iswrdi |  |-  ( U : ( 0 ..^ ( # ` W ) ) --> R -> U e. Word R ) | 
						
							| 10 | 8 9 | syl |  |-  ( W e. Word T -> U e. Word R ) |